I haven't really tried it yet with anything other than triggering samples. With the limited range, it's perfect for that. It could be good for running the solo section of the Streichfett and a polyphonic sequencer running the chord section. You can run chords to the polyphonic section using the drum sequencer, thinking about it, as the drum sequencer doesn't choke the last note played when a new note is triggered, then use Seq 1 or 2 to run the solo section to running the bassline or melody.
Oh yeah, it's worth mentioning also I've only run the drum sequencer using tied notes out of the drum-gate outs on the BSP so can't vouch for how well it runs over MIDI, but it imagine it'll work as I've not seen anyone complaining here that tied drum notes isn't working at all. I might have to extract my BSP from the modular and have a try running MIDI to my Streichfett again.